• 한국수소및신에너지학회논문집
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• 제30권3호
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• pp.209-219
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• 2019

Methanol is a liquid fuel which could also be produced from renewable energy sources and has appreciably high energy density. In this work, we investigated the application of $Ce_{0.9}Gd_{0.1}O_{2-x}$ supported Cu and Ni catalysts for hydrogen production via methanol steam reforming. Catalysts were synthesized by solution combustion synthesis. The prepared catalysts with various active materials and Cu loading amounts were tested in a reactor at $200-300^{\circ}C$, 0-5 barg range and steam to methanol molar ratio was 1.5. The catalytic properties of Cu and Ni were compared, and the catalytic performance was shown to depend on the amounts of metal loading and operating conditions such as reaction temperature and pressure.

• 스마트미디어저널
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• 제12권10호
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• pp.63-70
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• 2023

최근 스마트팜 에너지 비용 중 35% 낸난방비 에너지 소비가 증가되어 에너지 소비 효율화가 요구되며, 전기료 현실화에 대한 우려로 신재생 에너지 중요성이 증가하고 있다. 신재생 에너지는 수력, 풍력, 태양광 등에 속하며, 이중 태양광 에너지는 전기에너지로 변환하는 발전기술로, 이 기술은 에너지원이 환경에 미치는 영향이 적고, 유지 보수가 간편하다는 특징을 갖고 있다. 본 연구에서는 온실 축열조, 히트펌프 데이터 기반으로 축열조 영향을 많이 미치는 요소를 선정하고 축열조 공급 온도예측 모델을 개발하고자 한다. 시계열 데이터 분석 및 예측에 효과적인 LSTM(Long Short-Term Memory)과 다른 앙상블 학습 기법보다 뛰어난 XGBoost 모델을 이용하여 예측한다. 히트펌프 축열조 온도를 예측함으로써 에너지 소비를 최적화하여 시스템 운영을 최적화할 수 있다. 또한, 태양광 활용에 따른 냉난방비 절감 및 농가의 에너지 자립도 개선 등 스마트팜 에너지 통합 운영 시스템에 연계하고자 한다. 플랫폼을 통해 폐열 에너지의 공급을 관리하고 최대 난방부하 및 계절, 시간별 작물생장에 필요한 에너지값을 도출하여 이를 기반으로 최적 에너지 운용방안을 도출하고자 한다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.742-746
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• 2007

Energy environment has been changing rapidly such as high oil prices and the effectuation of UNFCCC. Oil prices have continued to rise and Dubai crude prices recorded 60 or 70 dollars per barrel in 2006. In addition, the effectuation of UNFCCC will affect Korean economy and national energy security. Korea is the 9th $CO_2$ emissions country and takes the 1st place related to the increase rate of $CO_2$ emissions globally. Energy technology development is a key breakthrough and one of the optimal alternatives to cope with national energy security. In this study, we prioritize energy technologies in the sectors of high oil prices and UNFCCC related to ETRM for well focus R&D and efficiency of finite resources allocations. We applied to the extended method of AHP, fuzzy AHP reflecting the fuzziness of human thoughts and perception, for prioritizing the relative importance among energy technologies in ETRM for the first time as we make an energy policy in Korea.

• 한국수소및신에너지학회논문집
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• 제34권5호
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• pp.535-548
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• 2023

The intermittent nature of renewable energy is a challenge to overcome for safety and stable performance in water electrolysis systems linked to renewable energy. Oxygen removal using the catalyst is suitable for maintaining the oxygen concentration in hydrogen below the explosive level (4%) even in intermittent power supply. Metals such as Pd, Pt, and Ni are expected to be effective materials due to their hydrogen affinity. The oxygen removal performance was compared under high hydrogen concentration conditions by loading on γ-Al₂O₃ with high reactivity and large surface area. The characteristics of the catalyst before and after the reaction were analyzed through X-ray diffraction, transmission electron microscope, H₂-temperature programmed reduction, X-ray photoelectron spectroscope, etc. The Pd catalyst that showed the best performance was able to lower 2% oxygen to less than 5 ppm. Changes in catalyst characteristics after the reaction indicate that oxygen vacancies are related to oxygen removal performance and catalyst deactivation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.609-614
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• 2005

Gas hydrates are ice-l ike sol id compounds that are composed of water and natural gas. All common gas hydrates belong to the three crystal structures that are composed of five polyhedral cavities formed by hydrogen bonded water molecules and stable in specific high pressure and low temperature conditions. Gas hydrates contain large amounts of organic carbon and widely occur in deep oceans and permafrost regions, and they may therefore represent a potential energy resource in the future. United States and Japan perform the national R&D programs for the commercial production of gas hydrates in 2010's. The study on gas hydrates are also important for exploration and development of natural gas in the regions where gas hydrates are accumulated and could be formed. Although their global abundance is debated, they play an important role in global climate change since methane is a 50 times more effect ive greenhouse gas than carbon dioxide. Natural gas hydrates also form a possible natural hazard if rapidly dissociated and can cause slides and slumps and in the marine environment associated tsunamis.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.43.1-43.1
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• 2010

In the crystalline silicon solar cells, the full area aluminum_back surface field(BSF) is routinely achieved through the screen-printing of aluminum paste and rapid firing. It is widely used in the industrial solar cell because of the simple and cost-effective process to suppress the overall recombination at the back surface. However, it still has limitations such as the relatively higher recombination rate and the low-to-moderate reflectance. In addition, it is difficult to apply it to thinner substrate due to wafer bowing. In the recent years, the dielectric back-passivated cell with local back contacts has been developed and implemented to overcome its disadvantages. Although it is successful to gain a lower value of surface recombination velocity(SRV), the series resistance($R_{series}$) becomes even more important than the conventional solar cell. That is, it is a trade off relationship between the SRV and the $R_{series}$ as a function of the contact size, the contact spacing and the geometry of the opening. Therefore it is essential to find the best compromise between them for the high efficiency solar cell. We have investigated the optimal design for the local back contact by using PC1D simulation.

• 한국해양환경ㆍ에너지학회지
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• 제16권3호
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• pp.217-225
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• 2013

환경문제가 심각해지고, 에너지안보에 대한 관심이 높아지면서 화석연료를 대체할 신재생에너지개발은 더욱 절실해지고 있다. 정부는 2030년까지 바이오에너지부분의 50%를 해양바이오에너지에서 생산한다는 계획을 발표하였다. 본 연구는 해양바이오에너지 개발사업으로 인하여 저감되는 온실가스의 저감편익을 조건부가치측정법을 이용하여 추정하고자 한다. 단일경계 양분선택형 모형에 스파이크 모형을 적용하였으며, 그 결과 해양바이오에너지 개발사업의 온실가스 저감편익은 단일경계 양분선택형에서는 가구당 평균 지불의사액이 4,190원으로 추정되었다. 이를 설문을 진행한 지역으로 확장하면 연간 501억원에 달한다. 이와 같은 연구결과는 해양바이오에너지 개발사업의 시행여부를 결정하는 비용편익분석이나 해양바이오에너지 개발사업정책에 있어서 편익의 유용한 정보로 활용할 수 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.153-156
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• 2006

The domestic solar radial ion data have been measured at 16 different sites all over the country since the beginning of 1980. It is very important that the fundamental data for the estimation and assessment of local solar radiation can be secured this project. In order to estimate available energy resource from solar radiation, it is necessary to have enough data, more than 30 years In any country. However since we have collected solar radiation(global radial ion including direct normal radiation) data only for 10 years we still need to measure insolation to secure the reliability and standardization of measured local solar radial ion data. In brief, the major activities on this R&D include rout me maintenance of the national network for insolation data measurement, evaluation of the collected data, and reliability enhancement for assessing the quality of solar radiation data as well.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.369-372
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• 2006

가스하이드레이트는 최근 고유가 시대에 기존화석에너지를 대처할 수 있는 가능성이 높은 에너지원이다. 이와 같은 이유로 정부는 2005년부터 본격적으로 가스하이드레이트 개발사업단을 발족시켜 국내의 부존형태와 매장량 평가를 위해 노력하고 있다. 2005년 2차원 정밀 물리탐사, 심해 퇴적물 채취 및 다각적 분석연구사업이 수행되었고, 2006년도에는 3차원 물리탐사, 심해 퇴적물 채취, 개발기술을 위한 연구 및 지질재해 안정성 연구등이 수행될 예정으로 있다. 사업단은 정부의 가스하이드레이트 개발 기본계획을 토대로 3단계 10개년 계획을 수행함으로써 미래 에너지원의 확보 및 자원 강국으로 가는 초석을 마련하려하고 있다. 향후 가스하이드레이트에 대한 관심사는 상업적 개발 가능성이다. 또한 대체 에너지들의 공통적 문제점인 막대한 비용 소요와 장기적 시간을 요한다는 점에서 여전히 문제점을 지니고 있다. 하지만 급속도로 발전하는 과학기술이 보조를 맞추어 준다면, 꿈의 에너지원인 가스하이드레이트가 모든 산업체와 가정에서 인류의 편안함을 지켜줄 시기가 도래할 것으로 기대해 본다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.553-556
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• 2007

Hyundai${\cdot}$Kia Motors have developed PEMFC stack technologies for passenger car application in 1998. The developed 80kW class stack, which was installed Kia's Sportage FCV in 2005, has been modified for -10$^{\circ}C$ cold start-up and ensuring the stability and durability by using new technologies such as newly designed separator, manifold block, end plate, and so on. And also, the stack durability has been verified over 1,500hrs with the condition of combined vehicle driving mode. Hyundai${\cdot}$Kia Motors will keep continuing the stack R&D to reach the goal of FCV commercialization.